Uxbridge seeks funding for sewer plant upgrade study

Sunday

Nov 10, 2013 at 6:00 AM

By Susan Spencer, TELEGRAM & GAZETTE STAFF

UXBRIDGE — As the town's aging wastewater treatment plant faces its day of reckoning to comply with new water quality standards, Director of Public Works Benn S. Sherman hopes voters will endorse spending $190,000 to study what upgrades would make the most sense.

Article 13 on the Nov. 19 fall town meeting warrant would authorize borrowing $190,000 for development of a comprehensive wastewater-management plan associated with new federal and state regulatory requirements.

Voters will also be asked to authorize transferring the money from wastewater retained earnings to the wastewater capital account, which would allow the town to spend the money up front if it doesn't receive borrowing authorization.

"When this was put in play, with the Clean Water Act, there was a big push and money to build wastewater treatment plants," Mr. Sherman said. "It's been 35 years, and things are showing their age. Unfortunately, the (federal) money's not there."

A preliminary analysis of upgrades to the sewer plant, conducted a few years ago, suggested an overhaul could cost up to $30 million. But Mr. Sherman said that was a worst-case scenario because no one knew what the new requirements would be.

The town received its final National Pollutant Discharge Elimination System permit in June from the U.S. Environmental Protection Agency and the state Department of Environmental Protection.

The permit, issued under the 1972 federal Clean Water Act, allows the public wastewater treatment facility to discharge water into the Blackstone River as long as it meets certain water quality standards.

The 2013 permit — the first issued to the town since 1999, despite an intended five-year cycle — tightens up the level of nutrients, including phosphorus and nitrogen, as well as toxic metals such as aluminum, that can be in the discharged water.

Excessive phosphorus and nitrogen, which come primarily from human and animal waste, fertilizer and agricultural runoff, cause aquatic plants and algae to grow abundantly, which in turn robs the water of oxygen for fish and marine wildlife, leading to dead zones. Phosphorus fuels excessive plant growth in freshwater, while nitrogen promotes it in saltwater, such as in Narragansett Bay.

The Blackstone River is listed by environmental regulators as an impaired water body. Causes for the impairment designation in the segment that the Uxbridge plant discharges into include, according to the NPDES permit, "unknown toxicity, priority organics, metals, nutrients, pH, flow alteration, pathogens, taste/odor/color, suspended solids and turbidity."

The Uxbridge permit also requires a comprehensive wastewater-management plan to assess long-term needs and wastewater treatment capacity. The most recent plan dates to 1969, with revisions in 1972 and 1975.

"It's going to look at the town as a whole, look at growth and potential expansion of the current collection system. It will give us a better idea of where we stand with the flow base," Mr. Sherman said.

Town officials filed appeals with the EPA Environmental Appeals Board and the state DEP when the permit was issued this summer, but they are holding off pursuing them while they negotiate with regulators.

Mr. Sherman said town representatives submitted comments on the draft NPDES permit after it came out in 2012.

"We were pleasantly surprised to see they incorporated some of our requests in there," he said.

A major change in the permit includes setting two tiers of nutrient limits, depending on how much wastewater is being treated on an average day.

The 1970s-era plant is designed to handle 2.5 million gallons per day. But Mr. Sherman said that at the time it was built, many of the old mills were still operating.

Current average use is much lower, averaging around 1 million gallons per day.

Under the new permit, when the plant treats lower average levels of wastewater, 1.25 million gallons per day or less, it doesn't have to meet year-round the stringent 0.2 (summer) to 1.0 milligrams per liter concentration of phosphorus, or the 8 milligrams per liter (summer) concentration of nitrogen required for higher flows.

Mr. Sherman said the town would want to design a system to more efficiently meet the actual and possible build-out needs.

Over the past few months, the wastewater-treatment plant has taken steps toward the new limits, including changing the chemical treatment to help reduce phosphorus and developing in-house laboratory operations for testing bacteria including E. coli and enterococci. The plant also has to measure and test discharged water year-round, when it previously didn't have to test in winter.

"They can see we're making good strides, and unlike some of the other plants, we've never made any upgrade," Mr. Sherman said. "We're definitely on the limit of technology of what it was designed for."

About 40 percent of the town's population is connected to the sewer system, Mr. Sherman said.

According to town Finance Director David A. Genereux, the projected annual cost to ratepayers to borrow $190,000 from the State Revolving Fund, which provides low-interest loans for water quality projects, would be between roughly $2 and $3 a year for 20 years, depending on interest rate, and $9 to $10 a year if borrowed over five years.

Contact Susan Spencer at susan.spencer@telegram.com. Follow her on Twitter @SusanSpencerTG.